From: near Philadelphia
What would be suitable for a good defense? Or does it all depends on the opponent and terrain?
The book says, "two up, one back, and feed them a hot".
But it really says what you said in your last sentence. METT Mission, enemy, troops, and terrain.
Keep in mind the penalty in dividing units (subunits have 80% of the parent unit proficiency, see Rule 8.2.11).
Avatar image was taken in hex 87,159 Vol 11 of
Vietnam Combat Operations by Stéphane MOUTIN LUYAT aka Boonierat.